Tuesday, November 19, 2013

Making a Gstring Backboard

SICgrips is committed to innovating and providing the most versatile training products for climbers. Our goal from the beginning has been to target products for people who aren’t able to put up a home climbing wall, who travel a lot, who want an alternative to the traditional hangboard, or who want more flexibility in mounting. This includes those (like students, renters, or those with fussy partners!) who can’t or don’t want to put holes in their walls. :-) When it's possible to feasibly market these products, we will. When it's not feasible for whatever reason, then we’ll provide basic instructions for the do-it-yourself types to make themselves. This is the first of several projects that we'll share over the next few months.

Gstring Backboard features:

  • provides a higher mounting point for the Gstrings, allowing more clearance for hanging
  • easy to put up and take down
  • provides a semi-rigid mount so Gstrings are similar to actual rock or hang boards.
  • stores easily behind an open door, in a closet or underneath a bed
  • easy to mount and dismount the Gstrings
  • cheap to make


While there are both permanent and temporary ways to mount Gstrings, we've heard from some users that when Gstrings are hung from a doorway pull-up bar, they don't have enough clearance to hang even with bent knees. The Gstring Backboard is one way to address this issue. It requires one of the many versions of popular doorway pull-up bars that cam and apply pressure to the top and front of the doorway trim and are easy to put up and take down. Many climbers already have one but if you don't, they can be purchased for $15-30 from sporting goods or department stores, or Ebay.

Items needed 
(total cost ~$15 depending upon what you have on hand):

  • modified Iron Gym-type pull-up bar (see below)
  • basic hand or power wood- and metal-working tools
  • 2' x 2' x ¾" piece of birch plywood (or equiv. hardwood)
  • 2" x 2" x 10' pine for Backboard frame and crossbar
  • #8 wood screws or 1 ½" nails
  • 2 pcs. - 5/16 " x 2 ½" lag screws (hang bolts for Gstring hang loops)
  • wood glue
  • 2 pcs. - ⅛" x  1.5" x 4" mild steel for pivot plates (available from your local hardware store in a 3' long strip)
  • 2 pcs. - ¼" x 2 ½ " hanger bolts with wing nuts and large washers for pivot plate
  • 2 pcs. - ¼  x 2" lag bolts with washers for pivot plate

Instructions
(This won't be a comprehensive step-by-step set of instructions because the Backboard is fairly simple to make. I'll cover a few specific things that may not be obvious.)

Modifying pull bar:


The dimensions given here are based on the doorway in my home. You’ll need to modify to fit your specific situation.
Remove the foam padding from indicated areas. Cut the horizontal handles off the pull-up bar with a hack saw or saber saw with a metal cutting blade, so there’s ¾" left beyond the center of the bolt hole. The photo shows ⅞", however ¾" is probably better so that it's doesn't run into the plywood backboard when mounted. (With the handles cut off, it can still be used as a pull-up bar using the center foam grip position).


Reverse the horizontal crossbar. Instead of it attaching to the bottom of the curved uprights (the normal way), attach it to the top of the crossbar. This will raise the backboard 2".



Cut plywood to 16" x 24". It could be made a bit taller (18" x 24") or it could be made slightly smaller 14" x 24"). If you have a wider piece of plywood, it could also be made as wide as your doorway). If you’re using the Backboard with the Gstring PROs, it will need to be at least 16” - 17” tall.







Drill a 1" hole in the vertical frame supports exactly in the middle lengthwise. Drill it so the edge of the hole is even with the edge of the wood. Remove excess from hole to edge of wood so that it becomes a 1" slot to slide onto the pull-up crossbar.












Drill a 5/16" hole in the pivot plate and then cut out a diagonal slot from the edge of the plate to the hole. This may need to be a little wider than 5/16" at the edge so it can pivot on the bolt and lock with the wingnut. The plate pivots open to mount on the pull-up bar and then close and lock with a couple turns of the wingnut.


 


 


Notes:
  • A washer was added to the hang loop to protect it from threads on the Backboard hang bolt. Then the hang loop was re-tied to make it as small as possible.
  • I added tape to bottom of board so the edge is more visible - anyone 5'11" or taller needs to duck :-)
  • I added a strip of yoga mat on ends of horizontal wood bar to protect the doorway from being scratched and dented. 
  • If you use the Backboard with Gstring PROs, you'll want to make sure
    that the board is at least 16"-17" tall because of their length. Instead of a vertically mounted hanger bolt, you'll want to use lag bolts and mount them horizontally at the top of the board face going into the top frame member. This will allow you to conveniently hang the 'biners on them.

Options:
  • t-nuts for mounting resin climbing holds, campus strips, or hangboard
  • a wider piece of plywood (up to width of doorway) can be used, though it will add weight and bulk). No matter what size of backboard you design, the pull-up horizontal bar should always be located in the middle vertically.
  • a set of hardwood edge strips could be added to simulate Eva Lopez's Progression or Transgression boards. Access to a table saw would be needed in order to accurately cut a set. The Gstrings could still be hung and accessed even with the edges if designed correctly. She has a done a lot of research and has come up with an effective finger strength training program based on this type of board. The drawback is that it only trains edges. However her blog has a wealth of information for training in general.

You might want to check our website to see examples of other non-permanent alternatives for mounting Gstrings if you haven’t already seen them :
In the near future we'll include instructions for how to make a similar type doorway mounted backboard, that doesn't use a pull-up bar. Stay tuned.

Disclaimer:
Make and use at your own risk. SICgrips makes no claims, explicit or implied, as to the safety of the Backboard for you and your situation because there are too many variables, including: strength of door frame casing; strength of doorway trim; climber’s weight and how the climber uses the backboard; what brand of pull-up bar is used and its strength rating; and the size, construction quality and materials used. When using the Backboard, do not use huge dynamic moments as it could stress the Backboard, pull-bar, and doorway beyond what it can hold. I am fairly light (135 lb.) so my use is not a good "yardstick" by which to determine your use of it. You can do a "hillbilly" test to help determine the strength of doorway trim by doing finger pull-ups on it to see how it reacts. This will stress it more than the backboard will. Gstring Climbing Grips are rated for climbers weighing 225 lb. or less. Therefore the Gstring Backboard combination should be below that limit. However, due to other factors mentioned above, it could be even less.





4 comments:

  1. Is this strong enough to screw a training board onto, and then use?

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  2. Is this strong enough to screw a training board onto, and then use?

    ReplyDelete
    Replies
    1. I have tried it. but if using 3/4" ply it should easily be able to hold that and work fine.

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  3. This comment has been removed by the author.

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